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epistemology of Aristotle

...(
On the Soul), Aristotle says that the intellect, like everything else, must have two parts: something analogous to matter and something analogous to form. The first of these is the
passive intellect; the second is active intellect, of which Aristotle speaks tersely. “Intellect in this sense is separable, impassible, unmixed, since it is in its essential nature activity....